I. Technical Field
The present invention relates generally to utilizing a housing of an electronic device as an input device, and more particularly to methods and apparatuses that provide measurement of a user's interaction with the housing of the electronic device.
II. Background Discussion
Electronic devices are ubiquitous in society and can be found in everything from wristwatches to computers. Depending upon the particular implementation of the electronic device, each device may have a different mechanism for interfacing with a user. Some electronic devices, such as laptop computers and mobile telephones, have dedicated portions of the device that include a standard keyboard where the user enters data by pressing one or more separate physical keys on the keyboard. However, as electronic devices and consumers become more sophisticated, many consumers prefer electronic devices with more aesthetically pleasing interface mechanisms. These aesthetically pleasing interfaces include touch pads and/or touch screens that do not have keys, buttons or other input mechanisms that physically protrude from the keyboard. Due to the lack of a conventional keyboard or other input mechanism, the user generally depresses certain designated areas of the touch pads and/or touch screens to interface with the electronic device. For example, many mobile telephones have touch screen interfaces, so that the user can contact with an area on the screen with a finger to enter a desired telephone number.
Conventional electronic devices often implement these touch pads and/or touch screens by relying upon capacitive coupling between the designed area of the device and a user. For example, in some conventional electronic devices, the capacitance or inductance of the user's hand or finger is measured to determine whether the user has made contact with the touch pad and/or touch screen. Unfortunately, there are many cases where the electrical characteristics of the user may provide an inaccurate representation of user's contact with the electrical device. For example, if the user is already touching or resting his hand on the touch pad and/or touch screen, then conventional electronic devices may already have measured this capacitance or inductance and be incapable of noticing the additional touch from the user. Also, the accuracy of measuring the electrical characteristics of the user may be compromised if the user's hand is not free of contaminants, (e.g., if the user has dirt or grease on his hands or his hand is sweaty). Furthermore, because conventional electronic devices register a user touching the touch pad and/or touch screen by detecting for the user's capacitance or inductance, conventional electronic devices are often incapable of determining the amount of pressure applied to the electronic device because the user's capacitance or inductance is generally unrelated to the pressure applied. Accordingly, methods and apparatuses that provide measurement of a user's interaction with the housing of an electronic device may be useful.